Geoege pay dailey



(Nb Model.)

I G. F. BAILEY.

AIR PUMP.

W, 0 e n u Tu d 9 t n 6 b a P 0mm 0 0 1 2 8 3 E w 0 I N n 9 H W"Attorney u. PETERS. Pnmmhu h. Wnhingion. a. Q

UNITED STATES PATENT OFFICE.

GEORGE FAY DAILEY, OF LEADVILLE, COLORADO.

AIR-PUMP.

SPECIFICATION forming part of Letters Patent No. 321,008, dated June 30,1885.

Application filed March 12, 1884.

To all whom it may concern:

Be it known that I, GEORGE F. DAILEY, of Leadville, in the county ofLake and State of Colorado, have invented certain new and usefulImprovements in Air-Pumps; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame;

My invention relates to improvements on the well-known Geisler mercuryair-pump, one of its objects being to dispense with all mechanicalvalves and cocks heretofore used in such pumps, and which have to agreat extent detracted from their efficiency by retaining, in the jointsand cavities incident to the construction of such valves and cooks,air,which expands in the pump and decreases the tension of the vacuum.It has the further object to provide novel means for the automaticreturn of the mercury to the movable reservoir after it has passedthrough the pump, and an additional object is to cheapen theconstruction and improve the general efficiency of this class ofair-pumps.

To these ends the invention consists in certain novel constructions andcombinations, which will be fully hereinafter described with referenceto the accompanying drawing, and definitely pointed out in the appendedclaims.

The drawing is a view, partly in elevation and partly in verticalsection, of a mercury air-pump provided with my improvements.

The letter A designates a bulb, preferably of glass, from the top ofwhich a tube, A, extends downward, said tube having a length from itshighest to its lowest point at least as great as that of the barometriccolumn of mercury at the place where the instrument is to be used, andit should preferably exceed this length two or three inches. At itslower end this tube enters a mercury seal-cup, C, which is supportedwithin and near the top of a stationary overflow-receiver, R, from thebottom or near the bottom of which leads a flexible tube, T, whichconnects with the upper part of a vertically-movable mercury-reservoir,M, which is open at its top.

From the lower end of the bulb A a short (No model.)

tube, 13, extends downward and enters a cup, K, from the bottom of whichextends downward a short tube, 70. The tube B is sealed into the cup Kby being passed snugly through an elastic stopper or plug, S, which isinserted in the upper partof this cup. There is also passed snuglythrough the stopper and into the part of the cup below it the lower endof a vertical tube, P, the upper end of which extends to a height abovethe highest point in tube A at least equal to, and preferably slight- 6oly in excess of, the barometric column of mercury, as before referredto. The short tube is at the bottom of cup K is jointed to aflexibletube, Q, by being inserted in one end thereof,

and the other end of this flexible tube is connected to the lower partof the vertically-movable lnercury-reservoir M A sealing-cup,w,surrounds the junction of the short tube and flexible tube Q, and is tobe filled with mereury above thejoint for the purpose of seal- 70 ingthe same air-tight. A slight space is also left above the ping S in thecup K to hold mercury for sealing the joints of the plug and cup and thejoints of the tubes passing through the plug.

From the point at which the tube T enters the mercury-reservoir M aspiral inclined tray or trough, 0, leads to the bottom of the reservoir,in order that the mercury may flow smoothly downward without having airincor- 8o porated with it, as would be the case if it fell abruptly fromthe tube to the lower part of the reservoir. A similar trough, o, leadsfrom an orifice near the top of the mercury seal-cup O to the bottom ofthe overflow-receiver R for the same purpose. These troughs may be madeof copper and will become amalgamated, so that as the mercury flows overthem no air will be likely to be caught in between the stream and troughwhen the mercury begins to flow.

The tube and vessels, except the mercuryreservoir M and the flexibletubes, are secured in the positions shown to a supporting-board, X, bythe usual means. A shelf is provided near the foot of the board, below 95' the reservoir It, for the mercuryreservoir M to rest upon when not inuse. The flexible tubes are preferably formed of india-rubher, and theother tubes and vessels may be made of any suitable material which willnot be dissolved or disintegrated by the mercury. Glass, porcelain,copper, or iron may be used, and if copper, the inner surface willbecome amalgamated, and securely airtightjoint will thus be alwaysmaintained between the'tubes and vessels and the mercury within them.

The operation of the improved pump as now described is as follows: Thereservoir M is to be filled with mercury, and when elevated above thebulb A, as shown in full lines, the mercury flows through the flexibletube Q and short tube It and enters the cup K, rising thence into bulb Aand tube P, reaching in the latter thelevel of the mercury in reservoirM. Forcing the air out of bulb A, the mercury overflows from this bulband flows down the tube A into the seal-cup G, from which it alsooverflows into the receiver R, passing down the spiral inclined trougho. A quantity always remains, however, in the tube A, having a heightequal to the barometric column or corresponding to the atmosphericpressure. The vessel to be exhausted is to be now connected by anair-tight joint to the top of tube P. If the reservoir M be now lowered,the level of mercury in tube P will also be lowered, and if thereservoir be lowered a sufficient distance the mercury divides at thetop of tube A, and, descending in bulb A, leaves a vacuum in this bulb,and at the same time the air from the vessel to be exhausted expandsbehind the descending mercury in tube P. Until the vacuum in this vesselis nearly complete, the mercury lowers faster in tube P than in bulb A,so that the air from the said vessel bubbles up through the mercury intobulb A. \Vhen the reservoir M has been lowered to the position shown bydottedlines, the mercury all leaves the bulb A and tube P, thus leavingfree communication between the bulb A and the vessel to be exhausted,the air from the said vessel being thus allowed to expand and becomehighly attenuated. WVhile the reservoir M is in its lowermost position,the mercury which has overflowed into reservoir R passes through theflexible tube T back to the reservoir, and runs down the inclined way'0, as before explained. The reservoir M, now replenished with mercury,is to be again raised, as at first, and the mercury, flowing into tube Band bulb A, forces the air out of the bulb through tube A, driving themercury out of said tube, and refilling it after the air has escaped.The mercury this time rises a little higher in the tube P, owing to theair in the vessel being partially exhausted. On again lowering thereservoir the operation already described is repeated. As the reservoirM is repeatedly raised, the mercury each time rises higher in the tubeP, and when the vacuum in the vessel to be exhausted is complete thelevel of the mercury in the said tube will stand about thirty inches, orthe height of the barometric column, above the level in the reservoir.The exhausted vessel may then be removed in the usual manner.

The discharge tube A should be of small and uniform caliber-say aboutone eighth of an inch or lessand dip below the level of the mercury inthe cup 0. Angles in this tube forming cavities should be avoided; henceit should connect with the highest point of bulb A.

The bulb A, tube A, reservoir M, and tube Q form, essentially, a Geislerair-pump; and the leading feature of my improvement is the combination,with such a pump, of the "ertical tube P, extending upward a sufficientdistance to prevent its overflowing when mercury is forced in the bulb Ain sufiicient quantity to force the air out through the discharge-tube Aor any other discharging de vice. Minor features will be pointed out inthe claims.

I'do not, of course, limit myself to the precise construction shown inmy drawing, but may vary the same in any manner not inconsistent withthe essential principles of my improvement.

Having fully described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l. The combination, with the bulb having a downwardly extendingdischarge tube connected to the upper end thereof, a mercuryvessel, inwhich said dischargetube terminates, and the exhaust-tube incommunication with the lower end of the bulb, and extending upwardly toor above the height of the barometric mercury column, of the movablereservoir, a flexible tube connecting the reservoir with theexhaust-tube and bulb, and a flexible tube leading from the upperportion of the reservoir to the lower part of the mercury-vessel, inwhich the discharge-tube terminates, substantially as set forth.

2. The combination, with a mercury-reservoir provided with an inlet atits upper portion and an outlet at its lower portion, of an inclined wayleading from the inlet to the lower portion of the reservoir,substantially as and for the purpose set forth.

3. The combination, with the Geisler pump having the short tube Bextending downward from its bulb, of the cup K, having its I lower endconnected by a flexible tube with the reservoir, and its upper portionprovided with a plug, through which the said short tube B and the lowerend of vertical tube P are sealed into said cup, substantially asdescribed.

4. The combination, with the bulb open at the top and bottom, adownwardly-extending tube connected to the upper end of the bulb, thevertically-movable reservoir communicating with the lower end of saidbulb through the intervention of a flexible tube, and a Vertical tube,P, communicating at its lower end with said reservoir and extend- Intestimony whereof I have signed this ing upwardly above the height ofthe barospecification in the presence of two subscrib- I0 metric mercurycolumn, of the mercury sealing witnesses. cup receiving the lower end ofthe downward- 5 ly-extending tube, the receiver inclosing the GEORGE FAYDAILEY' seal-cup, and a flexible tube connecting the Witnesses: receiverand movable reservoir, substantially W. 0. BROWN, as set forth. WM. M.ELLIS.

